The present disclosure relates to a thin-film device, a method of manufacturing the thin-film device, and a method of manufacturing an image display apparatus.
A field effect transistor (FET) includes thin-film transistor (TFT) which is currently used in many types of electronic equipment. For example, the FET has a configuration including a channel forming region and source/drain electrodes which are each formed in a silicon semiconductor substrate or a layer of a silicon semiconductor material, a gate insulating layer which is formed by using SiO2 on a surface of the silicon semiconductor substrate or layer of a silicon semiconductor material, and a gate electrode that is formed so as to face the channel forming layer through the gate insulating layer. The FET having this configuration is referred to as a top gate-type FET for convenience of description. Alternatively, the FET has another configuration including the gate electrode formed on a substrate, the gate insulating layer which is formed by using SiO2 so as to overlie the gate electrode and substrate, and the channel forming region and source/drain electrodes which are formed on the gate insulating layer. The FET having this configuration is referred to as a bottom gate-type FET for convenience of description. Expensive semiconductor-manufacturing equipment is used to produce the FET having such configurations, and the decrease of production costs is therefore strongly demanded.
In recent years, electronic devices in which a thin film made from an organic semiconductor material is used have been intensely developed, and organic electronic devices (hereinafter simply referred to as organic devices, where appropriate) such as an organic transistor, organic light emitting device, and organic solar battery attract attention. The organic devices are developed to finally provide advantages including reduced costs, reduced weight, sufficient elasticity, and high performance. As compared with inorganic materials typified by silicon, the organic semiconductor materials have several advantages such as: (1) enabling a large-area organic device to be produced through an easy process at low temperature, (2) enabling an elastic organic device to be produced, and (3) enabling the performance and physical properties of the organic devices to be controlled as a result of modifying molecules contained in organic materials into a desired form.
In particular, study of coating film-forming techniques such as a printing technique has been developed as an easy process at low temperature (see WO2003/016599).
In order to produce the organic devices through an easy process at low temperature, various types of layers other than an active layer (channel-forming region, for instance) are also obviously formed at a low temperature process. Therefore, a study has been advanced to form an insulating film from the organic materials (specifically a coating material formed as a result of melting a polymer), and a study has been similarly advanced to form various electrodes from a material containing dispersed metallic nanoparticles (specifically silver paste) which enable conductivity to be secured after being sintered at low temperature.